Aerodynamic Design and Performance of Nozzles with Different Mach Numbers Using Cfd Analysis
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INTERNATIONAL RESEARCH JOURNAL OF ENGINEERING AND TECHNOLOGY (IRJET) E-ISSN: 2395-0056 VOLUME: 05 ISSUE: 09 | SEP 2018 WWW.IRJET.NET P-ISSN: 2395-0072 AERODYNAMIC DESIGN AND PERFORMANCE OF NOZZLES WITH DIFFERENT MACH NUMBERS USING CFD ANALYSIS Vytla. Jayaprakash1, Alok Kumar Rohit2 , CH.Srinivas3, katrevula srikanth4 1Vytla jayaprakash, Department of Mechanical Engineering, Jain University, Karnataka, India 2DR. Alok Kumar Rohit, Department of Mechanical Engineering, Jain University, Karnataka, India 3Chilagani Srinivas, Department of Mechanical Engineering, Jain University, Karnataka, India 4Katrevula Srikanth, Department of Mechanical Engineering, Jain University, Karnataka, India ---------------------------------------------------------------------------***---------------------------------------------------------------------- Abstract— The exhaust nozzle system plays a flagship role 1.1 NOZZLE in aircraft and the design of nozzle have a supersonic cruise mission is optimized for a cruise condition and in takeoff conditions it must give the required quantity of thrust action at other most lynchpin operating points. In contrast, for a vehicle the exhaust nozzle system is to an accelerating mission must provide limited action across the flight envelop as there is not a fixed cruise point were the operates of aircraft the majority of the time. The aerodynamic design and performance analysis of convergent and convergent – divergent nozzle with different lengths 110.236mm and Fig-1: Water nozzle 135.636mm with subsonic and supersonic flow conditions is analyzed using CFD analysis. The comparisons are made for To control the direction of a fluid flow the device is used is pressure distribution, velocity and mass flow rates in 3D called as nozzle it exits (or enters) an enclosed chamber models are done in CATIA and CFD analysis or pipe. Key words— Nozzles, Cad, Mesh.CFD analysis. 1.2 AERODYNAMIC NOZZLE 1.INTRODUCTION We can metamorphose a gas turbine into a jet engine by utilizing the propelling nozzle. Power obtained from the While choosing the nozzles make sure its capabilities with gas turbine exited it can transfer into a high speed your current systems. The perform flow testing to ensure propelling jet by using the nozzles. Engines like turbofan you get adequate water and also consider the penetration may have spare and separated propelling nozzle which and reaction force on the firefighter. gives the high speed to propelling jet from the energy from To the extinguish a fire we will use the any nozzle, keep in the air is send through the fan. In addition, by using the mind that actual flow may be affected by many variables, nozzle we can determine how the gas generator and fan such as differences in piping from the pump to the operate as it acts as a downstream restrictor. discharge point, augment friction loss, changes in the types and their individual friction loss, different pump pressures, Propelling nozzles are moving quickly the obtained gas water supply issues and debris passing through the water to subsonic and transonic velocities rely on the power system. So be sure to test your nozzle under ideal setting of engine. The Convergent-divergent (C-D) are the conditions and under poor conditions to decide how it will internal shape which can move quickly the jet to works in both quality and inadequate of water-flow supersonic velocities within the divergent section, whereas situations. a convergent nozzle cannot accelerate the jet beyond sonic speed. By the characteristics of nozzles there are many features are available and uses. The key point is determining which 1.3 Types of nozzle nozzle is right for your needs. To help you make that determination, here’s a breakdown of some of the basic 1) Ejector nozzle nozzle types, and the pros and cons of each. Typically, the smooth-bore nozzle produces the greatest reach/rpm Ejector type of nozzle is used for pumping action of the combination of all nozzles while at the same time using the more scalding, high speed, engine exit entraining to an lowest engine pump ambient air flow. Nozzle manipulates the expansion of the exhaust of engine. 2) Thrust vectoring nozzle Nozzles for vectored thrust include fixed geometry Bristol Snidely Pegasus and variable geometry © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 951 INTERNATIONAL RESEARCH JOURNAL OF ENGINEERING AND TECHNOLOGY (IRJET) E-ISSN: 2395-0056 VOLUME: 05 ISSUE: 09 | SEP 2018 WWW.IRJET.NET P-ISSN: 2395-0072 3) Rocket nozzle Length 135.636 mm Rocket motors also used convergent-divergent nozzles, but 3d Sketch these are usually of fixed geometry, to minimize weight. 1.4 MACH In compressible flow theory the mesh is most flagship parameter, and it comparing with the speed of sound in a fluid (excellent measure of compressibility effects) and the speed at which the fluid is flowing. 1.5 MACH ANGLES This isentropic wave front is analogous to the oblique shock wave, and the angle between the wave front and the direction of the disturbance's motion is called the Mach Fig-3: Surface model wave angle or Mach angle. CONVERGENT DIVERGENT MODEL 2. INTRODUCTION TO CAD Length 110.236 mm As we know to design of an object in computer is difficult in computer in past days but now a day’s it’s so simple 2d Sketch firstly we know Computer-aided design (CAD) it is software now a day’s it’s made so easy to draw 2D and 3D Surface model diagrams in computers. It’s also called as computer-aided design and drafting (CADD).By the using of Computer The mach numbers or taken from the national aeronautics Aided Drafting which explains the drafting process in and space administration computer. For many of design engineering CADD software Mach number = is a flagship tool by using this software they shows the elegant designs of the objects as per the requirements. The output of CADD is in the form of print or machining THE SPEED OF SOUND C= 343 METERS PER operations. SECOND (M/S) The required output information is also important for CAD CFD ANALYSIS FOR AERODYNAMIC NOZZLE such as materials, processes, dimensions, and tolerances, according to specific applications. The design curves and CONVERGENT MODEL figures in two-dimensional (2D) space and solids surface in three-dimensional (3D) objects are shown in CAD FLUID –NITROGEN OXIDE software.. The design of geometric objects for object shapes, in particular, is often called computer-aided MODEL LENGTH – 110.236mm geometric design (CAGD).REID FLOW- SUBSONIC FLOW (MACH NUMBER 0.4) 3. 3D MODELING CONVERGENT MODEL Length 110.236 mm 2d Sketch Fig-2: Surface model Fig-4: Import model © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 952 INTERNATIONAL RESEARCH JOURNAL OF ENGINEERING AND TECHNOLOGY (IRJET) E-ISSN: 2395-0056 VOLUME: 05 ISSUE: 09 | SEP 2018 WWW.IRJET.NET P-ISSN: 2395-0072 Fig-5: Meshed model Specifying boundaries for inlet, outlet and wall Select edge → right click → create named section → enter name → inlet Fig-9: Velocity inlet Solution → Solution Initialization → Hybrid Initialization →done Run calculations → no of iterations = 30 → calculate → calculation complete as shown in Fig.9 Fig-6: Inlet Fig-10: Pressure difference graph Fig-7: Outlet Select edge → right click → create named section → enter name → outlet Wall Fig-11: Velocity Fig-8: Inlet and outlet of wall Select fluid nitrogen oxide Boundary conditions → select air inlet → Edit → Enter Inlet Velocity → 171.5m/s Fig-12: Reynolds number © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 953 INTERNATIONAL RESEARCH JOURNAL OF ENGINEERING AND TECHNOLOGY (IRJET) E-ISSN: 2395-0056 VOLUME: 05 ISSUE: 09 | SEP 2018 WWW.IRJET.NET P-ISSN: 2395-0072 Mass Flow Rate (kg/s) ---------------- -------------------- -------------------------------- -------------------- Net 0.001422882 Inlet 20.427063 Interior-part_1 -411.77686 CONVERGENT DIVERGENT MODEL Outlet -20.436523 FLUID –NITROGEN OXIDE Wall 0 MODEL LENGTH – 110.236mm ---------------- -------------------- Net -0.0094604492 MODEL LENGTH – 135.636 mm FLOW- SUPERSONIC FLOW (MACH NUMBER 1.0) Fig-16: Inlet Fig-13: pressure Fig-17: Outlet Fig-14: velocity Fig-18: Wall Select fluid nitrogen oxide Fig-15: Reynolds number Mass Flow Rate (kg/s) -------------------------------- -------------------- Inlet 40.853596 Interior-fill.1__ 272.28693 Outlet -40.852173 Wall 0 Fig-19: Select fluid nitrogen oxide © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 954 INTERNATIONAL RESEARCH JOURNAL OF ENGINEERING AND TECHNOLOGY (IRJET) E-ISSN: 2395-0056 VOLUME: 05 ISSUE: 09 | SEP 2018 WWW.IRJET.NET P-ISSN: 2395-0072 Wall 0 ---------------- -------------------- Net 0.026726723 FLOW-SUPER SONIC FLOW (MACH NUMBER 1.0) Fig-20: Velocity inlet FLOW- SUBSONIC FLOW (MACH NUMBER 1.0) Fig-24: Pressure Fig-21: Pressure Fig-25: Velocity Fig-22: Velocity Fig-26: Reynolds number Mass Flow Rate (kg/s) -------------------------------- -------------------- Inlet 27.960552 Interior-fill.1 -111.17674 Outlet -27.895111 Fig-23: Reynolds number Wall 0 Mass Flow Rate (kg/s) ---------------- -------------------- -------------------------------- -------------------- Net 0.065441132 Inlet 13.980276 MODEL LENGTH – 135.636mm Interior-fill.1__ -55.600498 Outlet -13.953549 © 2018, IRJET | Impact Factor value: 7.211 | ISO 9001:2008 Certified Journal | Page 955 INTERNATIONAL RESEARCH JOURNAL OF ENGINEERING AND TECHNOLOGY (IRJET) E-ISSN: 2395-0056 VOLUME: 05 ISSUE: 09 | SEP 2018 WWW.IRJET.NET P-ISSN: 2395-0072 RESULTS TABLE 1000 CONVERGENT 800 600 Table-1: Subsonic flow 400 200 Length Pressure Velocity Reynolds Mass 0 VELOCITY (mm) (Pa) (m/s) number flow Rate 110.236 135.636 (kg/s) LENGTH (mm) 110.23 89330.5 424.63 67365.2 0.000631 135.63 27530.2 264.28 45528.8 0.00944 Chart-2: Comparison of velocity values for different flows and lengths Table-2: Supersonic flow Length Pressure Velocity Reynolds Mass flow 150000 (mm) (Pa) (m/s) number Rate (kg/s) 100000 NUMBER 50000 110.236 357324.3 849.31 134740.1 0.0014228 CELL CELL REYNOLDS 0 135.63 110088.